The effect of electrical stimulation on healing and cell growth has been explored for decades. Clinical studies have shown improved fracture healing by using electric and electromagnetic fields as early as the 1970s. Disk electrodes coupled to the skin via conductive gel have been developed that generate and deliver a broad, noninvasive, capacitively coupled, and uniform electric field to the fracture site. The problem with conventional externally generated fields is that they cannot be directed preferentially to the fracture site, but rather are generally directed to large regions of an organism. Moreover, since the fields produced by conventional external electrodes are ordinary dipole fields the field strength diminishes with distance from the surface of the electrode. Thus, higher powers are required in order to deliver an effective field strength to the target cells.
Other art overcomes this problem by using implantable electrodes to localize the field, thus electrical regulation could be carried out in specific locations more efficiently, i.e. with waveforms having lower amplitudes and/or frequencies. This work used electrodes made from polymer-coated metals such as fluorocarbon-coated steel. However, such electrodes are not biodegradable/bioabsorbable therefore they require an additional surgery to remove them. Thus, the art is deficient in that it lacks an external electrode that is capable of delivering a localized electric field or current. Furthermore, the art lacks a biodegradable/bioabsorbable implantable device for generating therapeutic electric fields and/or currents.
The present invention fills this gap in the art by using patterned electrodes to create fields that are capable of being localized preferentially on the region of the organism where electric field or current delivery is indicated. Moreover, such electrodes can be made from conductive polymers (CP) that are biodegradable/bioabsorbable. Thus, the electrodes of the present invention can be implanted into an organism for therapeutic purposes, without requiring additional surgery to remove the same when the therapy is complete. Accordingly, the present invention fills a substantial gap in the art, and is novel, non-obvious and deserves broad patent protection.